This right-hand disc is the outer cutting element for a Mandam disc harrow. It is mounted at the end of the gang, where its angled profile slices the furrow wall to produce a clean, finished edge to the worked strip. The disc interacts with the soil at the boundary of the harrow’s working width; a worn or blunted outer disc leaves a ragged, un-cut furrow wall that reduces seedbed quality and increases draft load. This original Mandam component is formed to the same dish profile and hole pattern as the factory assembly, so it seats flush on the arbor without shimming. When replacing, inspect the arbor bushings and torque the retaining nut to specification.